Amides of fluorinated propionic



Patented July 11, 1950 7 AMIDES OFFLUgR INATED CIDS rnoriomc I David W. Chaney, Nether Providence Township, Delaware County, 'Pa., assignor to American Viscose Corporation, Wilmington, Del., a cor poration of Delaware No Drawing Application June 4,

. Serial No. 31,206

3 Claims: (01. 260 561) l This invention relates to amides of fluorinated propionic acids of the general formula in which X is selected from the group consistin of fluorine and chlorine.

This application is a continuation-in-part of my pending application, Serial No. 680,055, filed June 28, 1946, now Patent No. 2,456,768.

The new fluorinated amides are obtained from corresponding fluorinated propionyl chlorides, or fluorides by reaction of the halide with ammonia.

The fluorinated propionyl'halides are obtained by oxidizing propylenes of the formula by passing a stream of oxygen, preferably mixed with a small amount of chlorine gas as catalyst for the reaction, into a vessel containing the propylene and equipped with suitable stirring ,means and a, source of internal actinic radiation such as a mercury vapor lamp encased in a quartz tube extending into the vessel. The gas is passed in until the acyl halide is formed, as indicated by a marked decrease in the gas absorption rate,,

and usually a time varying f om 50 hours to 120 hours, depending upon the propylenebeing oxidized, and other conditions such as the efficiency of stirring, the concentration of chlorine used, and the intensity of the radiation.

The temperature at which the oxidation is conducted may vary somewhat, depending upon the boiling point of the propylene being oxidized and the solubilities of the gases therein, which decrease with increasing temperature, but is preferably maintained within the range of from about to 80 C., the reaction vessel being externally cooled to dissipate the heat of the actinic radiation source.

The reaction of oxygen with the propylenes of the type under consideration apparently results in the formation of an intermediate oxide of the general formula orgxoxc 01.

where X has the same significance as above,

which by rearrangement involving a shiftv of a halogen atom from one carbon to another, is

converted to the corresponding acyl halide. Most unexpectedly, this shift of a halogen atom and rearrangement to form the acid halide takes place, in the case of the propylenes under consideration, not only with respect to chlorine, but under the conditions described herein, with respect to the perhalogenated methyl group. Thus, when 1,1,3 trichloro 2,3,3 trifluoro propeneprcductcomprises both the acid chloride (CF2ClCFClCOC1) and the acid fluoride (CFzClCClzCOF), the former due to a shift of the chlorine atom, the latter due to a shift of CFzCl, the rearrangement taking place according to the following scheme:

First step-Oxidation o OFzC1CF=QCh 0130101 0011 l 0 Second st'ep Rearra ngement (1) Shift of chlorine v 1,. v cracloro I (2) Shift of substituted methyl group x. 320103001; 0F201001200F The oxide or mixture ofoxides present in the reaction product may be converted to the acyl chloride or mixture of acyl'chloride and acyl fluoride by treatment with an amine such as .pyridine or, in the case of non-fluorine contain- 'ing compounds, by treatment with Friedel-Crafts type salts.

The new fluorinated amides may be obtained by treating the oxidation reaction product directlyiwith ammonia, or the acyl halides may be separated from the oxidation reaction mixture prior to treating them with ammonia, if desired. The amides are useful as intermediates in various chemical processes. For example, the amides may be dehydrated to produce fluorinated acrylonitriles capable of forming ethers by direct addition of an'alcohol to the double bond.

,. The following examples in which the parts are by weight will serve toillustrate the invention.

4 -Ewample I The apparatus" used was a three-neck flask "equippedwith a stirring device, thermometer, gas inlet, reflux condenser, and a source of internal actini-c radiation comprising an watt mercury vapor lamp encased in a quartz tube extending into the flask. About 2,785 parts of 1,1,2,3-tetrachloro-3,3-difluoro-propene-1, (CF2C1CC1=CC12), were placed in the flask and a mixture of oxygen and chlorine in a 10:1 ratio was passed into the flask with constant stirring of the flask contents. The temperature was held at 45-450 C., the flask being cooled by means of running water. At the start, the gases-were' absorbed at, arrate of 50 mL/min'; After 'about'20 hours, theab'sorption rate had dropped to about ml./min. and the reaction was terminated.

The reaction liquid comprisesgprimarilyz'calichloro-p-difiuoro-chloropropionyl chloride,

CFzClCClzGQCl and an oxide believed to be orlolo c1001,

The crude oxidation product obtained was 'diluted with dry ether, and dry ammonia waspassed into the mixture. The-reaction was exothermic and the mixture Was maintained at a. temperature -bel-ow' C. bycooling'itwith"iceiwater, and continuous stirring. The FinS'oluble ammonium salts which precipitated were Jfiltered off andrepeatedly extracted with ether. Upon evaporation of the combined ether filtrate and extracts a stickysolid separated which was dried under vacuum. On distillation under vacuum,- dichloro-,9-difiuorochloropropionamide (CF'zGlCCl'zCONHu) was obtained, B. P. 135-148/29 mm., M. P.,

Example II 100 parts of the amide described in Example I in powdered form,-were.intimately"mixed in a flask with 150 parts of powdered phosphorous pentoxide and the mixturewas heated to 150-160" C. in an oil bath. The nitrile was distilled off as it formed. At the end offivehours,the'tempemture was allowed to rise to 210 C. 84 parts of distillate were collected in a receiver cooled by ice, washed with dilute sodium bicarbonate, then with water, dried over sodium sulfate and distilled.

m1./min. When the absorption rate dropped to about 50 ml./rnin., which required about hours, the reaction was terminated.

The contents of the flask were then slowly heated "to about "50C. to reiiioye Jdissolved chlorine "gasand low-boiling by-products.

The crude reaction mixture was diluted with 1500 parts of dry ether, cooled to 10 C., and dry -.-ammonia was-passed into the mixture with conyg'stant stirring. The reaction between the acid halides and ammonia was exothermic, the tem- Jperaturebeing maintained at below 20 C'. by ex- "iternalcoolin'g.."After about 8 to 10 hours, the acid halides were converted to the correspondin amides and insoluble ammonium halides. The in- :solublehalideswere filtered oil", and extracted with ether. The filtrate and ether extracts were All of the product" distilled btweerf91-95 c. A

pure sample of a-dichloro-c-difiuorochloropropionitrile had a boiling point of 95 C., freezing point 32.5 C., and refractive index ihe reaction mixture also comprised" some funoxidized starting material, some chlorinated product', and lay-products resulting from"more complete oxidation and degradation, including C0012, CO, and CF-zClCOCl. The temperature during the reaction was maintained at about.,35 C. The 10 to'l mixture pf gaseous'oxiygenand chlorine gas was absorbed at" the"rate"of"'300 combined, and dried finally under vacuum.

2710 parts of a mixture of amides consisting of a-chlorofluoro-fl-difluorochloropropionamide, and

'a dichloro-p-difluorochloropropionamide were obtained. :"Ewample IV parts of. the. amides obtained imaccordance with the procedure described'dn Example-IIL'Zin finely powdered condition were "intimately .mixed with partsof powderedphosphorous pentoxide in a round-bottom flask. The mixture was. heated to -180" C. in an oil bath. -:-At ithat xtemperature, the product beganto distil over. Heating .was continued foriabout3four-zhours;;the tempera- :ture beingi'finally raised to.'200;C. wAbeutTlfi parts of crude distillateiwere obtained. oThevdi'stillate was washed twicevwithice water, dried over anhydrous sodium s'ulfate; aiid distilled. At 46-56 'Iclaim: i

-1. Amides of fluorinated propionic': acids of the formula "CFzClCClXCONHz where X is selected from the group consisting of fluorine and chlorine. 2. Alpha, alpha dichloro betmbeta 'difiuoro- -beta chloroprcpionamide. v

3. Alpha 'chlo'ro, alpha If fluoro=beta;betadifluoro-beta chloropropionamide.

' DAVID W:CHAN'EY.

1 -:4REFERENCES cor-ran The'following references are of recordin the file of this patent:

UNITED STATES PATENTS Number Name Date 2,292,129 Kirkbride 'Aug. 4, 1942 2,332,302 D'Alelio ".Oct. 19, 1943 3 2,409,315 Rigbyet al.v a Oct. 15, 1946 2,426,891 .3-Lynch Sept. 2, 1947 2,427,624 Rushmer et al. "nus-"Sept. 16, 1947 2,438,200 Behr et al, Mar. 23, 1948 2,439,505 Chaney Apr. 13, 1948 2,456,768 Chaney Dec. 21, 1943 g OTHER-REFERENCES 'RichtersOr gani'c" Chemistry, vol. 1 (1944) page 1321. 

1. AMIDES OF FLUORINATED PROPIONIC ACIDS OF THE FORMULA CF2C1CC1XCONH2 WHERE X IS SELECTED FROM THE GROUP CONSISTING OF FLUORINE AND CHLORINE. 